Update: In-case anyone has found an active interest in my love life.
Last Friday (Feb 23) 3 friends and I got together to see the new Die Hard movie (I don't recommend it). My girlfriend didn't come along and instead invited the other friend in question. He was hesitant at first but he came along. We ended up having a good time, all 4 of us stopped for some fast food before hand, we all joked around like normal. Everything was good. To me it still felt like there was an elephant in the room the whole time, but I wanted to leave it up to him to bring the situation up if he wanted. He obviously didn't because we didn't talk about it. So, maybe things are back to normal? I haven't talked to him since that night but it seamed ok to me. I'm sure he's still dealing with something
Side note: I linked this thread to my girlfriend and she agrees with how I've been approaching it and with the views of most of you.